2023年6月25日发(作者：)
Adobe® Media Server 5 White Paper
Table of contents
1: Introduction
2: What’s new in
Adobe Media Server
5
3: Adobe Media Server 5
Family
4: MultiProtocol delivery
6: Delivery Methods
7: Video Player
Development
8: Glossary
9: Online Resources
Introducing Adobe® Media Server 5
Secure video experiences consistent across devices
By Lisa Larson-Kelley
The Adobe Media family of products revolutionizes media delivery, with support for secure, consistent
streaming on the widest array of devices—tablets, mobile devices, IPTV, and the desktop. Deliver and nowencrypt a single stream across multiple platforms and protocols, reaching iOS devices as well as platforms
that support Flash technologies—so you can fully monetize your video, reaching the most people with the
least hassle. Adobe Media Server (formerly Flash Media Server) continues to be the industry-leading
solution for integrating streaming video and real-time communication with RTMP, RTMFP (peer-to-peer
networking), HTTP Dynamic Streaming, and SIP support.
New content protection solutions
Providing content protection that is right for the situation, Adobe Media Server now supports enhanced
stream encryption or more sophisticated protection with business rules applied through Adobe Access®.
When simple content protection rules are needed, Protected HTTP Dynamic Streaming (PHDS) for
Flash and AIR-based clients, and Protected HTTP Live Streaming (PHLS) for iOS enable easy, robust
content encryption without an additional DRM license server. For mobile devices, Adobe Access or
protected streaming can be used within AIR applications or native iOS applications.
Enhanced server management and media preparation
With the release of Adobe Media Server 5 software, customers benefit further from new features such as:
More robust media origin services
Advanced disk management for HTTP streaming
Offline stream packaging
Dynamic copy protection
Real-time data sharing, server-side plug-ins, logging, and monitoring APIs provide developers and IT
teams with the tools they need to develop and administer rich media applications on a massive scale.
Adobe® Media Server 5 software provides a simplified HTTP publishing workflow that allows you to deliver
video to iOS, AIR and Flash Player quickly and easily. Flexible delivery methods can save significant
bandwidth costs and lighten network load. Enhancements in integrated real-time communication open up
new business opportunities, with high quality voice and video capabilities providing access to a universe
of SIP-enabled devices. From user-generated content to movies and television shows to corporate training
and large-scale internal broadcasts, Adobe Media Server offers enterprise-level solutions for delivering
content and communications. Improved performance and quality of service metrics enhance playback
quality, while included prebuilt media players make deployment easier than ever.
This white paper outlines the powerful features of Adobe Media Server 5, explains protection options,
introduces the various editions, and discusses the features available in each and how they can lower your
total cost of delivery and simplify your content preparation workflows. You will learn about the multiple
delivery protocols supported by Adobe Media Server, and gain the knowledge you need to make informed
choices about how to deliver and monetize video and communication services to the largest online
audience.
What’s New in Adobe Media Server 5
Adobe Media Server 5 is a scalable, real-time media origin server that packages and delivers high quality
(up to HD level), on-demand and live audio/video content with great efficiency and superior quality-of-
service (QoS) to reach the largest possible audience, regardless of the client platform. It can deliver
prerecorded video, live video, playlists, music, video blogging, video messaging, multimedia chat
environments,
real-time datacasting, multiuser gaming, and more, via multiple delivery protocols.
Adobe Media Server now streams securely to Apple iOS, Flash Player, and Adobe AIR across platforms,
browsers, and devices, with multiple protocols available. Enhanced real-time communication now features
SIP Gateway support in Flash Player and Adobe AIR, along with RTMP and RTMFP protocols.
Adobe Media Server 5 has many improvements and new features, including:
Expanded media streaming options
Protected RTMP (pRTMP)
24/7 live streaming support
Adobe Access key rotation and output protection (Adobe Access license required)
Protected HTTP Dynamic Streaming for Adobe Flash and AIR (PHDS)
Protected HTTP Live Streaming for Apple iOS (PHLS)
Adaptive bitrate manifest support
Multi-protocol manifest generator/pre-packaging tools (Flash and iOS)
Adobe Access 4 DRM ready
608/708 closed captioning support
Enhanced communication features
On-demand stream packaging for HTTP (Flash and iOS)
Audio extraction for HLS (required for Apple App Store approval)
SIP Gateway support with G711 coding in Flash Player
High quality audio/video capture support
Scalable P2P introduction services for Flash
Multicast ingest and recording
Server platform
Robust HTTP Media Origin services
Advanced disk management for HTTP (Flash and iOS)
Optimized Server configuration for live HDS
Native 64-bit only
These improvements represent the continued evolution of Adobe Media Server, giving developers the
advanced features they need to create effective rich media applications across platforms and devices. In
addition, OSMF reduces the learning curve and speeds up your time to market.
Adobe Media Server 5 Family
There are four Adobe Media Server 5 editions available:
• Adobe Media Server 5 DevelopmentStarter (free from Adobe)
• Adobe Media Server 5 Standard
• Adobe Media Server 5 Professional
• Adobe Media Server 5 Extended
Adobe Media Server 5 Professional and Adobe Media Server 5 Extended can operate as either an origin
or an edge server to distribute traffic load. Enhanced media origin services allow greater control over
media publishing workflows for HTTP streaming to Adobe AIR, Flash Player and Apple iOS. For more
details on origin and edge configurations, see the “Scaling the server” section of the Adobe Media Server
5 Technical Overview white paper (/go/ams_techguide).
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The following table provides a quick overview of supported features in each edition. Features supported in
all editions are highlighted in bold.
Adobe Media Adobe Media
Feature Server 5 Server 5
Adobe Media Adobe Media
Extended Professional
Server 5 Server 5 Starter
Standard
HD live streaming
24/7 Live streaming support
using DRM key rotation
• • • •
HTTP Live Streaming for iOS
(HLS)
• • • Limited to 30 min
Stream reconnect • • • •
Live stream metadata (data
keyframes)
• • • •
Live adaptive bitrate
streaming (HTTP)
• • • Limited to 30 min
Multicast ingest and
recording
• • •
Live 608/708 closed caption
support
• • • •
High quality video capture • • 1 way only •
Live stream splitting • • •
Live adaptive bitrate Limited to 10
streaming (RTMP) • •
simultaneous
connections
DVR functionality (HTTP) • • Limited to 30 min
DVR functionality (RTMP) • • •
Instant replay (RTMP) • • •
Linear server playlists
(VOD>live)
• • •
IP Multicast • • Limited to 30 min
Application-level multicast • • Limited to 30 min
Multicast fusion (peer assist) • Limited to 30 min
HD on-demand streaming
Standalone offline packaging
utilities (HDS and HLS)
• • • •
Stream reconnect
In-buffering seeking (RTMP)
Fast forward
Available in all versions of Adobe Media Server 5
Slow motion
to enable high quality streaming across the whole product offering
Framestepping
Back buffer for instant replay
VOD adaptive bitrate
streaming (HTTP)
• • • Limited to 30 min
VOD 608/708 closed caption
support
• • • •
VOD adaptive bitrate Limited to 10
streaming (RTMP) • • •
simultaneous
connections
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Adobe Media Adobe Media
Feature Server 5 Server 5
Adobe Media Adobe Media
Extended Professional
Server 5 Server 5 Starter
Standard
Content Protection
Offline packaging and
encryption (HDS and HLS)
• • • •
Protected RTMP (pRTMP)
• • • •
Protected HTTP Dynamic
Streaming for Flash (PHDS) • • Limited to 30 min
Protected HTTP Live
Streaming for iOS (PHLS) • • Limited to 30 min
Adobe Access 4DRM
ready
• • •
Encrypted RTMP (RTMPe) • • •
• SWF verification • • •
• Adobe Access streaming • • •
•
RTMFP (encrypted)
•
Limited to 500
Limited to 50
peers
peers
IP multicast (encrypted) • • Limited to 30 min
Server platform and security
64 bit Windows®, Linux only
• • • •
White/Black list domains
• • • •
IPV4, IPV6
• • • •
C++ access
control
• •
Access C++
plug-in only
•
extensibilityPre-configured HTTP origin
for HTTP Dynamic Streaming
• • • •
LDAP Active Directory
support
• • •
Scalable process scopes
• •
•
RTMP edge caching
• •
•
C++ file management
extensibility
• •
•
Quality of service
Robust logging
• • • •
Enhanced buffer control
• • • •
Bandwidth detection
• • • •
RTMP QoS (DiffServ) Linux only Linux only Linux only Linux only
Enhanced caching
• •
•
Licensing
Processor (CPU) limits None None None None
Bandwidth limits None None None None
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Adobe Media Adobe Media
Feature Server 5 Server 5
Adobe Media Adobe Media
Extended Professional
Server 5 Server 5
Standard Starter
Connection limits
• 25 SIP
• 5 SIP • 50 simultaneous
connections connections RTMP
• 15,000
(development
connections
simultaneous
only)
• 50 simultaneous
RTMFP peers
• 500
RTMFP peers
simultaneous
• 30 minutes of IP
RTMFP peers
multicast
• 30 minutes of
HDS, HLS, pHDS,
and pHLS
• 5 SIP
connections
Interactive programming
Server-side record
• • •
Shared objects
• • •
Data push
• • •
Socket server ingest
• • •
Server proxy programming
• • •
Peer introduction forwarding
• • •
Peer-assisted networking Limited to 15,000 Limited to 500 Limited to 50
(RTMFP) peers peers peers
Custom server-side
programming
• • •
AMF3 support
• • •
Unified communications
SIP gateway services
Limited to 25 Limited to 5 Limited to 5
simultaneous simultaneous simultaneous
connections connections connections
VoIP
• • •
Webcam chat
• • •
RTMFP unicast
•
Limited to 500
peers
•
RTMFP peer introduction Limited to 15,000 Limited to 500 Limited to 50
services peers peers peers
RTMFP object replication
•
Limited to 50
peers
RTMFP posting/directed
routing
•
The following sections explore the capabilities of each server to help you select the best solution for your
specific application.
Adobe Media Server 5 Starter
Adobe Media Server 5 Starter enables developers to test and develop using the features of Adobe Media
Server 5 Extended. Full functionality with a few connectivity limitations allows you to test drive features such
as protected HTTP streaming, SIP gateway services, peer assisted networking, multicast fusion streaming,
and new multicast ingest and recording. This free edition is available from /go/
tryadobemediaserver. It can be used in production for anyone who wants to implement basic low-volume
streaming or social communication solutions. It has a capacity limit of 50 simultaneous inbound RTMP
connections, 50 peer introductions, 30 minutes of IP multicast, 5 SIP ports, and 30 minutes of continuous
HLS and HDS protected streaming.
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Adobe Media Server 5 Standard
Adobe Media Server 5 Standard is an economical solution that enables you to start streaming live and on
demand content quickly and easily to a wide variety of platforms and devices, including iOS. It provides all
the features you need to stream video and audio, and works in unison with the Adobe Flash Media Live
Encoder to stream live video. This edition is ideal for:
Basic video on demand (VOD) and live streaming
Publishers who wish to simplify their content preparation workflow
Small to medium-size businesses that want to implement training or broadcast
Bloggers who want to broadcast live or on-demand streams
Videographers who need to allow clients to securely view their videos on the web
Company-wide video messages
Website owners who want to embed and protect high-quality streaming video
One-way, secure video streaming
Adobe Media Streaming Server 5 ships with three services that make it easy to start streaming right out of
the box:
Live video streaming—The included live video RTMP streaming application allows you to start publishing
live video right away. It works with the Adobe Flash Media Live Encoder for live stream capture. You can
use Flash Media Playback, Strobe Media Playback, and custom OSMF-based players for to play the
streams.
Video on demand—The standard RTMP VOD application features server-to-client bandwidth detection,
domain-based authentication, full support for Flash Media Playback and custom OSMF-based players.
The server ships with sample media files for testing.
HTTP Live Packager—The HTTP Live Packager (livepkgr) application ingests streams, such as from Flash
Media Live Encoder, packages them into fragments, and delivers the fragments to clients in real-time.
Both the live and VOD applications support the stream data access feature in Flash Media Server 3 and
later (all editions), which allows you to access the bitmap data of a stream. This feature has a myriad of
uses, such as taking snapshots from a webcam feed or creating thumbnails or video previews dynamically.
Adobe Media Server 5 Professional
Take advantage of even greater levels of content protection across more devices with Protected HTTP
streaming – which takes advantage of Adobe Access 4 (a separate server purchase) – and deliver rich
interactive experiences with added peer assisted networking support. Enhance your applications with
custom functionality, record streams, utilize remote shared objects, leverage peer assisted networking,
and access additional scalability features.
Adobe Media Server 5 Professional offers powerful network efficiencies with support for IP multicast,
RTMFP, HTTP Dynamic Streaming for the Flash platform, and HTTP Live Streaming for Apple iOS.
Automated packaging enables delivery to iOS, Flash Player 10.1 enabled browsers and devices, and AIR
with no additional workflow complexity. This edition provides consistent, secure interactive playback
experiences and real-time communication across the broadest range of platforms and devices. It is ideal
for:
Medium to large businesses that can benefit from flexible delivery methods
Publishers who wish to simplify their content preparation workflow, with enhanced DRM protection
Social media companies requiring multiuser experiences
Companies that need to maximize delivery capacity while minimizing network costs
Large-scale deployment
Developing custom video solutions, including stream recording and DVR functionality
Developing communication experiences
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Supplementing live or on-demand video streaming services with interactive features
Adobe Media Server Professional lets you include value-added multi-way solutions to help you socialize
your streaming media with advanced real-time communication and collaboration services. It’s the only high-performance and scalable server on the market that supports multi-way applications, including webcam
video chat, recording, VoIP, and online games. Adobe Media Server Professional is the workhorse of the
Adobe Media family, and even features support for peer assisted networking (RTMFP).
Adobe Media Server Professional can also be used to interact with specialty data servers such as LDAP
for authentication, Simple Object Access Protocol (SOAP), or XML, and integrates with Adobe Flash
Media Live Encoder. For even more customization, you can also implement custom server-side
ActionScript and develop plug-ins in C++ that further extend the functionality of the server.
In addition to the features in the Adobe Media Server Standard edition, Adobe Media Server 5 Professional
includes additional streaming and communication features such as:
Application-level multicast
IP multicast broadcast
Multicast Fusion (for more information, see the “Benefits of Each Delivery Method” section later in this
document)
Scalable RTMFP peer introduction and routing services for Flash (500 peers)
Protected HTTP streaming for Apple iOS, Android, Flash Player, and Adobe AIR.
Scalability with Edge caching
Adobe Media Server 5 Extended
Adobe Media Server 5 Extended provides maximum reach with minimum network load through peer
assisted networking support. Adobe Media Gateway functionality is integrated with this edition enabling
connection between Flash and SIP-enabled devices. Designed to use the network more efficiently for large-scale media delivery and real-time communication, Adobe Media Server 5 Extended is ideal for:
Large broadcasters who want to reach the widest audiences with protected content, including Apple iOS
Large enterprises with large global networks
Massive social media applications
VoIP services that want to integrate traditional calls with Flash applications
Companies that need to maximize delivery capacity while minimizing network costs
Large enterprises with media requirements over multiple locations and networks
Customer-facing marketing (such as press conferences or product demos)
Enterprises that want complete control over their media delivery
Companies that want to reach the widest range of platforms and devices and automate content preparation
In addition to the features in other editions, Adobe Media Server 5 Extended includes advanced streaming
and communication features such as:
Support for SIP-enabled devices (25 connections)
Scalable RTMFP peer introduction and routing services for Flash Player and AIR (15,000 peers)
Multiprotocol Delivery
Adobe’s traditional streaming protocol, RTMP, has served and protected millions of hours of video and
enabled revolutionary interactive experiences. Adobe Media Server 5 introduces support for an even
wider range of delivery protocols and formats, providing a consistent, secure playback experience across
platforms and devices.
Adobe® Media Server 5 White Paper
7 Video delivery and consumption is becoming increasingly fragmented and complex, with clients of
differing protocols, screen sizes, and processor capabilities. Delivering video with Adobe Media Server
reduces the complexity of media publishing, offering the publisher a very simple workflow to publish and
encrypt video across Apple iOS, Android, connected TVs, and the desktop. With on demand packaging
that will automatically convert streams for HTTP delivery, you can depend upon consistent codec support,
protection, and a high-quality experience regardless of the device or platform.
The following table outlines supported transport protocols, delivery methods, and associated server versions.
Transport
Adobe Media
Adobe Media
Adobe Media Adobe Media
Protocol
Delivery Method
Server Standard
Server
Professional
Server Extended Server Starter
RTMFP Unicast Limited to 500
• Limited to 50
peers
peers
Native IP
• • Limited to 30 min
multicast
Peer-assisted
• • Limited to 30 min
(application-level
multicast)
Multicast fusion • • Limited to 30 min
Multicast ingest
• • •
and recording
HTTP Progressive
• • • •
download
HTTP Dynamic
• • • Limited to 30 min
Streaming (HDS)
HTTP Live
• • • Limited to 30 min
Streaming for
Apple iOS (HLS)
Protected HTTP
• • Limited to 30 min
Dynamic
Streaming (pHDS)
for Flash Player
and AIR
Protected HTTP
• • Limited to 30 min
Live Streaming
(pHLS) for Apple
iOS
RTMP pRTMP • • • •
RTMP • • • •
RTMPE • • • •
RTMPT • • • •
RTMPS (SSL) • • • •
The Flash Platform for video delivery
Flash Player has evolved along with Adobe Media Server. With Flash Player 10.3 and later, the client
runtime supports an array of new video-related features. Coupled with Adobe Media Server 5, the Flash
Platform now has the ability to stream video and enables communications to more screens than ever
before. You can achieve maximum reach with the ubiquitous Flash Player in the browser, Flash Player
10.1 on select devices, and Adobe AIR on the desktop and devices.
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Introduced in Flash Player 10.3, Media Measurement for Adobe® Flash® allows companies to measure
video usage more easily. Get real-time, aggregated reporting of how video content is distributed, what the
audience reach is, and how much video is played. With Adobe Flash Player 10.3 and Adobe SiteCatalyst®,
powered by Omniture®, developers can implement video analytics for websites with as little as two lines of
code. Analytics solution providers can use a set of new open APIs to easily implement consistent video
analytics regardless of implementation or delivery protocol.
Flash Player 11 and AIR 3 now support major video enhancements, including multi-threaded video
decoding and H.264/AVC video encoding. Multi-threaded video decoding enables improved playback
performance and increased frame rates of high bitrate content, for both live streaming and real-time video
chats on Windows, Mac OS, and Linux. Enjoy higher-quality video capture with H.264/AVC video encoding
right in the browser.
Recent audio enhancements include G.711 audio compression for SIP Gateway communication in Flash
Player 11 and later, and acoustic echo cancelation in the desktop version of Flash Player 10.3 and later.
Support interoperability with legacy phone systems via the Adobe Media Gateway (AMG) and other third-party clients (through the open RTMP protocol) without the need for transcoding. Create real-time
online collaboration experiences with high-quality audio, such as telephony, in-game voice chat, and group
conferencing applications for desktop PCs. Developers can take advantage of acoustic echo cancellation,
noise suppression, voice activity detection, and automatic compensation for various microphone input levels.
End users will be able to experience higher quality audio, facilitating smoother conversation flow, without
using a headset.
Adobe Media Server support for versions of Adobe Flash Player
Features
Versions Versions Version Version Version Version Version
8 and 9 9,0,115,0 10 10.1 10.2 10.3 11
G.711 audio compression for
•
telephony (SIP Gateway
support)
H.264/AVC software •
encoding for cameras
Multi-threaded video •
decoding
Protected HTTP Dynamic • •
Streaming (pHDS)
Media Measurement • •
(desktop only)
Acoustic echo cancellation • •
(desktop only)
IP Multicast • • • •
HTTP Dynamic Streaming • • • •
RTMFP Groups • • • •
RTMFP • • • • •
Multicast fusion • • • •
Adobe Access Protection • • • •
Stage Video GPU hardware
• • • •
acceleration (including Mac
support)
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Features
Versions Versions Version Version Version Version Version
8 and 9 9,0,115,0 10 10.1 10.2 10.3 11
Stream Reconnect/Buffer
• • • •
access/Trick modes (fast
forward, rewind, back buffer)
Sorenson Video (H.263) with
• • • • • • •
Nellymoser audio—play and
capture
On2 VP6 video codec: play
• • • • • • •
only
H.264 and High Efficiency
• • • • • •
AAC: play only
RTMPE / RTMPTE • • • • • •
SWF Verification • • • • • •
Limited GPU hardware
• • • • • •
acceleration
Multicore support • • • • • •
Smart buffering (in-buffer
• • • • • •
seeking)
RTMP Dynamic
• • • • •
Streaming (Adaptive
Bitrate)
XMP metadata • • • • •
Speed audio codec • • • • •
Flash Player support in versions of Adobe AIR
Flash Player 9 Flash Player 10 Flash Player 10.1 Flash Player 10.3 Flash Player 11
AIR 1.0
•
AIR 1.5
• •
AIR 2.0
• • •
AIR 2.5
• • •
AIR 2.7
• • • •
AIR 3.0
• • • • •
Adobe AIR (version 1.0 or later) for playback clients
Adobe AIR is a cross-operating system runtime that enables you to use your existing HTML, Ajax, Flex,
or Flash web development skills and tools to build and deploy rich Internet applications (RIAs) across
platforms and devices—including Android™, BlackBerry®, iOS devices, personal computers, and televisions.
Adobe AIR applications support native operating-system integration, including clipboard and drag-and-
drop support, local file input and output, and system notification. AIR applications can connect to Adobe
Media Server to stream audio and video or share data, just as SWF files do. Adobe Access content
protection is supported as well.
Adobe AIR 3 compatibility
Adobe AIR 3
Flash Player 11 features
•
Open Source Media Framework
•
(External plug-ins not supported)
Adobe Access 4 Integration
•
For more information about Adobe AIR visit /products/air/. For details about
supported desktop and mobile operating systems and specifications, see
/products/air/ systemreqs/.
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Delivery Methods
Adobe Media Server 5 supports delivery to Flash Player, AIR, and iOS clients. There are two supported
methods for delivering video over the Internet to iOS:
HTTP Live Streaming (HLS)
Protected HTTP Live Streaming for (PHLS)
There are seven methods for delivering video over the Internet to Adobe Flash Player and AIR clients:
Embedded video
HTTP progressive download
RTMP streaming (pRTMP, RTMPe, RTMPS, RTMPT)
HTTP Dynamic Streaming (HDS) for the Flash Platform
Protected HTTP Dynamic Streaming (PHDS)
Multicast streaming (native IP multicast, application-level multicast, multicast fusion)
Although this section focuses on delivering video files, these same methods can be used to deliver audio-only
experiences.
Embedded video adds video directly to a SWF file and is used for very specialized applications with low-quality, short video clips.
In both progressive download and streaming delivery, the video content is external to the SWF file. To
deploy on-demand video content to the web, the SWF file and the video files are uploaded to a server.
Keeping the video external and separate from the video player offers a number of benefits over the embedded
video method:
High quality experiences with multi-bitrate
Protected experiences
Reduced client memory usage
Advanced streaming options that improve the experience, such as live video, enhanced seeking, large
file support, and alternative delivery such as HTTP Dynamic Streaming
Improved player performance overall
Lower SWF size
Faster playback startup time
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Progressive download has been supported for video delivery since Flash Player 7 (released in 2004).
This method allows developers to load external video files into a Flash Player or Flex interface and play
them back during runtime. In this approach, the video is downloaded like any other file, and then played
back. This can be accomplished using the ActionScript Video object, OSMF, or by setting parameters of
feature- rich prebuilt players such as Strobe Media Playback, as shown in the following figure.
Adobe Media Server has a built-in Apache server with configurations that can make it very easy to
transition from progressive download to streaming.
Figure 1
Strobe Media Playback is an open-source implementation of the Open Source Media Framework, offering support for set-level manifests and
other OSMF 1.6 features. Configurable via ActionScript or flashvars.
With progressive download, when the video is played, the video file first begins to download to the user’s
hard drive, and playback starts when enough of it has been downloaded for buffering. The video file is
served from a standard web server through an HTTP request, just like a regular web page or any other
downloadable document.
In comparison to streaming video, progressive download has only one consistent benefit: You don’t need
a streaming server to deliver the video. It can be served from any typical web server.
While this can be convenient and potentially cost-effective, there are some potential issues:
Limited seek and navigation capabilities
Often the entire video file is downloaded, even if the viewer did not play back the entire file, wasting
bandwidth
Viewers can access and repurpose the content on the local hard disk.
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When to choose progressive download
Progressive download is a good choice for hobbyists or websites that have low traffic requirements, if they
don’t mind their content being cached on a user’s computer, they only need to deliver videos less than 3
minutes long, or their visitors cannot receive streaming video for some reason.
You should stream your video if you need to do the following:
Take advantage of advanced features and control over video delivery
Display higher quality video
Deliver videos with long durations (more than 3 minutes)
Deliver high volume
Track and report usage or viewing statistics
Offer viewers the best interactive playback experience.
Avoid cache-raiding and content repurposing, due to the fact that progressive delivery leaves the video
file in the browser cache.
Deliver the highest quality possible with adaptive streaming.
Specific use cases for progressive delivery include:
Publishers of short video clips, such as video blogs
Publishers who don’t need real-time content protection (Adobe Access can be used to protect content
delivered via progressive delivery)
Individuals or companies that have low-volume media delivery requirements
Streaming delivery also consumes less bandwidth than progressive delivery, because only the portion of
the video that is watched is actually delivered.
RTMP streaming
The ability to stream video and audio was first available with Flash Player 6.
Publishers use video player applications such as Strobe Media Playback to deliver video. Strobe Media
Playback supports RTMP streaming, HTTP Dynamic Streaming, and progressive download. Video files
are stored external to the (Strobe) playback application SWF for these delivery methods. Plug-ins that
enable simple integration with third-party APIs and add features such as in-stream advertising and
analytics are available. Developers can use OSMF to take advantage of the latest Adobe Media Player
features and further customize their player applications with ActionScript commands that extend
functionality.
Flash Player manages streaming video in a similar way to progressive downloaded video. For example,
video data is loaded into a video player application from an external source, is played back using
NetStream class, and can be controlled via ActionScript. However, streaming video over RTMP requires
a persistent connection to the server and cannot operate without a network connection. This connection
provides additional benefits, including better memory management and no resident video files on the
client computer.
This tight connection between the server and the client, and the server’s ability to precisely control and
deliver any portion of a stream as requested, enables the developer to take advantage of some advanced
capabilities.
Large-scale live streaming—Creating webcast live or recorded events where all viewers access the same content
at the same time.
QoS—Measuring and tracking the stream’s quality of delivery and switching to a lower (or higher) bitrate
stream if needed (for example, if network congestion increases).
Dynamic previews—Automatically generating thumbnails or playing short previews of your video clip
without having to create separate images or video clips, and without downloading the entire video in the
background.
Dynamic chapter navigation—Automatically creating “chapters” (with appropriate thumbnails) that can
be used for navigation of longer videos, without having to break the video into smaller files.
Stream swapping—Seamlessly switching midstream from one camera angle or one stream to another.
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On-the-fly editing—Piecing video clips together to create one continuous video for playback. For
example, playing the first 10 seconds of clip 1, followed by the content between the 30- and 40-second
marks of clip 2, followed by the last 20 seconds of clip 3.
Bandwidth detection—Determining the client bandwidth and serving a stream with an appropriate bitrate.
RTMP streaming benefits
RTMP streaming provides the publisher many more options for high-quality video and protected media
delivery and interactive video experiences.
The advantages of streaming video from Adobe Media Server are numerous:
Real-time content protection—Simple workflow to encrypt and protect streams, with options to increase
protection with Adobe Access file encryption.
Faster start—Fastest way to start playing any video on the web.
In-buffer seeking for fast response time—Instant seeking within the buffer with the new buffer access
feature in Flash Player 10.1 and later.
Stream reconnect—Uninterrupted playback experiences when connectivity with the server is lost; play
through the buffer while automatically reconnecting.
Simple content-protection workflows—Protect video with a wide range of solutions from encrypted
RTMP (RTMPe) to Adobe Access encryption.
Low-latency live video—Deliver live video and audio from any connected webcam or DV camera, and
even directly from some video cards, natively in Flash Player.
Advanced video control—Features such as bandwidth detection, QoS monitoring, automatic thumbnail
creation, server-side playlists, and more.
Efficient use of network resources—Customers who pay for their video hosting or bandwidth by the number
of bits that are transferred can reduce costs because only the bits that the client actually views are transferred.
More secure, protected media delivery—Because the media data is not saved to the client’s cache when
streamed, viewers can’t retrieve the video or audio file from their temporary Internet file folder. Additional security
features in Adobe Media Server 5 also prevent stream ripping and other risks.
Minimal use of client resources—Less memory and disk space used because the client doesn’t need to
download and store the entire file.
Tracking, reporting, and logging capabilities—Because progressive download is a simple download of a file,
it’s not easy to log relevant statistics such as how long the video was viewed, if the user navigated forward,
backward, or paused the video, how many times the viewer played the video, if the viewer left the webpage
before the video completed playing, and so on. Streaming enables you to easily capture this important data.
Full seek and navigation—Because viewers can seek to any point in the video and start playing immediately
from that point, streaming is a great solution for longer-playing videos or uses such as video blogging,
classroom lectures, and conference sessions, where viewers want to jump to a specific point rather than being
required to watch from the beginning.
Deep interactivity—Streaming’s precise control lets developers create extensive interaction in their video
applications. For example, the ability to switch camera angles, have one video spawn another video, or
seamlessly switch to alternate endings, are all enabled by streaming.
Video capture and record (Adobe Media Server Professional and Adobe Media Server Extended
only)—Record video either in conjunction with the live stream, such as archiving an event, or on its own,
such as video messaging.
Multiuser capabilities (Adobe Media Server Professional and Adobe Media Server Extended only)—In addition to live one-to-many streaming, Adobe Media Server enables multiuser streaming of audio,
video, and data for the creation of video communication applications.
Adobe® Media Server 5 White Paper
14
RTMP streaming and progressive download delivery methods are very similar to deploy. Streaming just
gives the developer more power to create rich, interactive video applications. Flash Media Playback can
be used for either delivery method. If more customization or the most current playback features are
required, OSMF or Strobe Media Playback can be used.
Video publishers who have high-volume streaming needs, popular content, or critical uptime requirements
but don’t want to build their own infrastructure can get the benefits of streaming video in Flash Player by
utilizing a content delivery network (CDN). These Adobe partners offer load-balanced, redundant
deployment of Adobe Media Server over a reliable content-delivery network. For more information about
cdn partners, visit /go/ams_partners
When to choose RTMP streaming
You can use streaming with Adobe Media Server in situations where you need to do the following:
Deliver files longer than 3 minutes or larger than 100Kbps
Protect content in real time with RTMPe and SWF Verification, and PRMTP (with Adobe Media Server 5.1
Extended).
Broadcast low-latency live streams
Provide adaptive bitrate delivery, allowing you to deliver the best quality video for the available hard- ware and
connection speed
Monitor QoS
Perform real-time tracking
Integrate real-time data sharing and interactivity to your video experiences
Stream live video and audio
Record video and audio
Serve more streams with less bandwidth
Achieve massive scale delivery
If your website or blog relies heavily on video, audio, or real-time data sharing, you can give your user the
best experience by using the features of Adobe Media Server. Examples of typical use cases for RTMP
streaming include:
Medium to large businesses that could benefit from complex deployment requirements such as edge,
origin, C++, SSAS, ACL, or LDAP
Social networks requiring real-time communication, such as video chat, VoIP, multiplayer games, or text
chat alongside video content
Educational institutions that want to create a virtual classroom or broadcast live, interactive experiences
Government agencies that want to implement real-time communication or interactive training
News broadcasters streaming live programming
Podcasters who need to accurately measure viewership and interaction
Sports broadcasters that want to enable DVR functionality
Anyone seeking scalable, secure streaming with custom server-side application logic
Adobe® Media Server 5 White Paper
15 HTTP Dynamic Streaming (HDS) for the Flash Platform [ENHANCED]
Flash Player 10.1 introduced support for HTTP Dynamic Streaming, enabling an adaptive-bitrate,
protected streaming experience with common HTTP servers, caching devices, and networks. Functionality
and performance are similar to RTMP streaming, but a streaming server is not required. Using a standard
MPEG-4 fragment container format, HTTP Dynamic Streaming supports both live and on-demand media
content that adjusts to the viewer’s connection speed and processing power. It is compatible with standard
HTTP protocol infrastructures that can scale efficiently and affordably.
A key enhancement in Adobe Media Server 5 is in the just-in-time packager, which now provides real-time
packaging of content for HTTP streaming delivery from the same recording application. The Apache
module () efficiently handles the creation of fragments and manifests needed for both HTTP
Dynamic Streaming and HTTP Live Streaming delivery simultaneously, enabling playback across a wide
range of devices with a single media source. For PHDS/PHLS delivery, the fragments are now recorded
unencrypted on disk, and then encrypted dynamically for HDS or HLS.
The following tools to process and deliver content via HTTP Dynamic Streaming are included in the Adobe
Media Server 5 installation:
File Packager for VOD—Creates MP4-fragmented media (F4F) and the manifest file (F4M) from existing
content encoded for Flash technology. The tool also optionally encrypts using Adobe Access. (in amsroot/
tools)
Live Packager—Prebuilt service that converts any RTMP live stream into protected F4F files to create a
streaming experience over HTTP. The tool also optionally encrypts using Adobe Access. (in amsroot/
applications)
HTTP Origin Services built on Apache—The Apache web server has been preconfigured as an
HTTP origin server, making it easy to serve F4F files to content delivery networks (CDNs) or your own
HTTP infrastructure. (in amsroot/Apache2.2/modules)
Set-level F4M/M3U8 Generator (f4mconfig)—SWF file that assists in creating multi-level manifests for both
HDS and HLS delivery. (in amsroot/tools)
Video players that are built using OSMF, such as Flash Media Playback and Strobe Media Playback,
provide the player logic required to parse and play media sets and manifest files, request media, monitor
QoS, and render playback. Strobe Media Playback supports the latest technologies such as multi-level
manifests generated via the f4mconfig tool.
Benefits of HDS
HTTP Dynamic Streaming reproduces much of the functionality of RTMP delivery, providing the publisher
a choice in delivery options. The primary benefit that HTTP offers is its ability to cache content, which is
important for enterprise customers who deploy internal caching systems to optimize network usage to
increase capacity of delivery over the public Internet without increasing cost (with optimized CDN
configuration).
HTTP Dynamic Streaming can enable significant improvements over progressive delivery. Some of the
benefits of HTTP Dynamic Streaming over HTTP progressive download include the following:
Delivery cost reduction by using the Internet caching infrastructure
Higher burstable capacity using standard CDN load-balanced networks and HTTP infrastructure caching
Support for adaptive bitrate, DVR, and integrated content protection powered by Adobe Access on live
streams
Content protection throughout the distribution chain, closing some potential vulnerabilities
Rapid, custom video player development through OSMF, which offers built-in logic and easy integration
with advertising and analytics
Bitrate throttling, adapting to available network and hardware capacity
Saves bandwidth; ensuring that only what is watched is delivered
More flexible media navigation, including enhanced seeking and start-anywhere
Adobe® Media Server 5 White Paper
16
HTTP Dynamic Streaming considerations include:
Flash Player 10.1 or later is required. For Flash Player penetration statistics, visit /
products/player_census/flashplayer/version_.
The F4F format is only compatible with HDS-compatible players or others that support the MPEG-4 fragment
format. The same files cannot yet be delivered using RTMP streaming or progressive download.
Additional workflow steps (i.e. real-time or pre-processing of fragments and manifests) are required to
prepare content.
Adobe Access 2 or later is required for content protection.
Live streams experience increased latency when compared with RTMP streaming due to the media
fragmen¬tation and encryption process before delivery.
When to choose HDS
Examples of use cases for HTTP Dynamic Streaming include the following:
Adaptive streaming behind restrictive firewalls
Massive-scale live broadcasting
Enhanced seeking over standard HTTP connections
Enterprise streaming on existing network infrastructure
HTTP Live Streaming for Apple iOS (HLS)
Flash Media Server 4.5 introduced support for streaming to Apple iOS devices such as iPhone and iPad
via Apple’s HTTP Live Streaming (HLS). HLS is simple to configure and requires no additional steps in
your workflow. On demand and live streams are packaged when the user requests them, in the proper
format for playback either natively in iOS or through HTML5 in the browser. If you wish to pre-process
your files for HLS playback, a new tool included with Adobe Media Server 5 enables this, creating the
required fragment and manifest files.
To use HLS to serve live streams to clients over HTTP, publish the streams to the HTTP Live Packager
service on Adobe Media Server (rootinstall/applications/livepkgr). The livepkgr service ingests the streams,
then the HLS module (mod_hlshttp) repackages the fragments into MPEG2-TS segments, and delivers
them to iOS clients (via HLS). The Origin module (f4fhttp) delivers F4F fragments to Flash clients (via
HDS). This is all done in real-time.
Benefits of HLS
With devices becoming more and more popular for media consumption, it is important for your content to
be available on every device. Support for HLS packaging in Adobe Media Server 5 now enables you to
reach those viewers using iOS without having to reencode your on demand content or create separate live
streams.
When to choose HLS
Since no additional encoding steps are required, you can now easily deliver HLS streams alongside HDS
and RTMP for full compatibility with every platform and device. Adobe Media Server even helps you
comply with Apple App Store guidelines by producing the required audio-only file for each stream.
The HLS video stream can be played in HTML5 in the browser, or in a native iOS app written in Objective-C, or in AIR on iOS. When playing the streams using an HTML5 player, however, you will lose many
features such as sophisticated interactivity, timed-text captioning, stream encryption, and other
custom aspects you may have built into your Flash-based player application. Some of this interactivity can
be rebuilt using JavaScript and HTML, but compatibility across browsers becomes an issue; for example,
only Safari running on a Mac or on iOS will play HLS streams in HTML5. You can still protect your streams
using file encryption with Protected HTTP Live Streaming (see following section) across all of these
playback methods.
Examples of use cases for HLS include the following:
Live streaming of events to devices
On demand streaming to devices
Adaptive streaming using a set-level variant playlist file
Adobe® Media Server 5 White Paper
17
Protected HTTP streaming [ENHANCED]
Flash Media Server 4.5 introduced Protected HTTP Dynamic Streaming for Flash and AIR, enabling DRM
protection without requiring a license server, and Protected HTTP Live Streaming for Apple iOS, enabling
AES-128 wire protection (but no DRM support). It utilizes limited Adobe Access policies, built right into the
server. Adobe Media Server 5 Professional and Extended now support this level of DRM protection for
both HDS and HLS, for both on-demand and live streams. Protected HTTP streaming is an alternative to
full-featured Adobe Access protection,
In addition to encrypting content for delivery to Flash Player and AIR, PHDS also supports SWF verification
for HTTP Dynamic Streaming.
The real-time packaging process for on-demand and live Protected HTTP Streaming generates a license,
embeds it in the DRM metadata, and delivers it with the media—eliminating the need for communication
between the client and a License Server. This process is initiated when a player client requests the
protected stream over HTTP; Adobe Media Server will then encrypt the fragments as they are sent and
create the required license.
Benefits of Protected HTTP Streaming
What is unique about Adobe Media Server’s approach is that the license is part of the video itself. This is
a very scalable solution, since the keys are delivered and cached over HTTP. Encrypting your content
with Protected HTTP Streaming is a relatively simple process, and it allows you to set specific viewing
windows—even for offline playback and downloaded content. Content preparation tools are included with
Adobe Media Server, giving you a straightforward workflow for delivering scalable protected content over
HTTP to Flash, AIR, and iOS.
When to choose Protected HTTP Streaming
Examples of use cases for Protected HTTP Streaming include the following:
Content supported by advertising
Protected live broadcasts on the desktop and devices
Protected live and on-demand playback on iOS
Protected live and on-demand playback on the desktop in AIR
Protected playback on Flash Player-enabled devices supporting Adobe Flash Player 11, or in-app playback in
AIR on devices.
If your content requires more sophisticated DRM rules, you can also use Adobe Access 4 in conjunction
with Adobe Media Server, for both HDS and HLS delivery.
Multicast streaming [ENHANCED]
Multicast streaming, introduced in Flash Player 10.1 and Flash Media Server 4, enables the distribution of
NetStreams across peer-to-peer connections, and powers IP multicast over UDP. The stream can be
audio, video, or even a data stream. Multicast is a network-efficient delivery method that uses existing
multicast- enabled network hardware to deliver large internal broadcasts without overwhelming the
network. The most common use case is live video, but it can be used to deliver on-demand video. Adobe
Media Server ships with a Multicast configurator tool that assists in setting up multicast broadcasts.
Benefits over unicast (RTMP or HTTP)
Multicast can provide huge network efficiencies, dramatically reducing the use of bandwidth and server
resources, resulting in lower total cost of delivery. It can also provide ultra-low latency for sharing video,
audio, and data over networks enabled with multicast support. A major benefit is that RTMFP is an
inherently secure protocol. It uses 128-bit DH keys for all communication and SHA256 hash of the client’s
DH key for peerIDs. For more information about RTMFP security, consult the following references:
RTMFP FAQ: “How does RTMFP address security and end-user privacy?” /
products/adobe-media-enterprise/
Best practices for real-time collaboration using Flash Media Server, by Joszef Vass (.
com/devnet/flashmediaserver/articles/)
RTMFP sections in the Adobe Media Server 5 Developer’s Guide.
Adobe® Media Server 5 White Paper
18 When to choose multicast
Multicast is the obvious delivery solution for enterprise, especially those with networks enabled with
multicast support. It can also be useful for multiplayer gaming, because it provides very low latency.
Ultimately, it is useful for any application where multiple clients want to receive the same media at the
same time, including:
Inter-office videoconferencing
Company-wide broadcasts
Real-time financial or news tickers
Medium to large companies that need to maximize delivery capacity while minimizing network costs
Large enterprises with media requirements over multiple locations and networks
Key multicast concepts
Three types of multicast delivery are available:
Application-level (P2P) multicast
Native IP multicast
Multicast fusion (An Adobe innovation that increases the quality, reach, and network efficiency of live video
delivery.)
Application-level multicast, sometimes referred to as P2P multicast, provides an optimized stream
distribution among peers, via RTMFP connections. This approach can be very cost-effective because the
stream payload is distributed among the peers rather than taxing your servers and network. The original
stream can be distributed either from a client or from Adobe Media Server. Application-level multicast can
help reduce bandwidth costs for product marketing, user-generated content, or internal broadcasts. It is
supported in Adobe Media Server Professional and Adobe Media Server Extended.
Native IP multicast enables businesses to use existing multicast-enabled networks to deliver large internal
broadcasts without overwhelming the network. Adobe Media Server supports both SSM (source-specific)
and ASM (any source) multicast. This approach is best for internal, enterprise, VPN, or LAN networks with
multicast-enabled hardware in place.
Multicast fusion is an innovative combination of native IP and application-level multicast. Available in
Adobe Media Server Professional and Adobe Media Server Extended, multicast fusion allows employees
to receive live video via IP multicast and use those clients to help distribute to employees not connected
to a multicast-enabled network. This approach is best for large organizations broadcasting both internally
and externally. Figure 2 illustrates a multicast fusion deployment, where internal clients are receiving the
stream via hardware-based Native IP multicast, and clients outside the network are receiving the stream
via based Application-level multicast. The incoming live stream is published to Adobe Media Server over
RTMP, and all clients are receiving streams over RTMFP. Notice that the clients are also communicating
between each other, helping to share the load.
Adobe® Media Server 5 White Paper
19 Figure 2
Multicast fusion overview
Adobe Media Server 5 ships with a Configurator tool that makes multicast publishing very simple. The tool
lets you create an IP multicast, application-level multicast, or multicast fusion broadcast with the incoming
stream being sent to the server via Flash Media Live Encoder. The Configurator generates a standard
manifest (F4M) file that can be used with Flash Media Playback, Strobe Media Playback, or a custom
OSMF player, so you can get started streaming high-quality video quickly.
Figure 3
Multicast Configurator tool
Adobe® Media Server 5 White Paper
20
RTMFP and peer-assisted networking [ENHANCED]
Adobe Media Server 5 enables peer introductions as well as support for the RTMFP Groups technology in
Flash Player 10.1 and later. This technology reduces the demand for server bandwidth, opening up
possibilities for new types of multiuser applications, such as video chat and other real-time media
applications that may have been previously hindered by bandwidth costs. For more details about RTMFP
Groups, see Peer-assisted networking using RTMFP groups in Flash Player 10.1, by David Hassoun and
Jun Heider: /devnet/flashmediaserver/articles/p2p_rtmfp_.
Peer-to-peer introductions enable Flash Player and AIR clients to establish a connection with other Flash/
AIR clients to start sharing data and media over RTMFP. This introduction service, which had been
available only via the Cirrus service (previously named Stratus), is now a feature of Adobe Media Server
Professional and Adobe Media Server Extended. RTMFP Groups support is also available in both Adobe
Media Server Professional and Adobe Media Server Extended.
Benefits of RTMFP and peer-assisted networking
The most significant benefit of peer-assisted networking is the offloading of network traffic from the server
to the client, which results in significant bandwidth and infrastructure cost savings. While latency might be
slightly higher than with RTMP streaming, it is lower than with HTTP Dynamic Streaming.
RTMFP Groups adds new posting and directed routing features to basic peer-assisted networking,
allowing any client participating in a group to broadcast data to the rest of the group or even target a
specific client. Object replication, another powerful feature of RTMFP Groups, allows all members of a
group to maintain a consistent view of a potentially large set of objects. This provides low-latency data-sharing that can be used for applications such as social media and real-time games. The efficient topology
of RTMFP Groups allows developers to achieve massive scale, because routing through a single peer or
server cluster is not required.
Peer-assisted networking through Flash Player is a secure, managed communication solution. The
client’s peerID is generated as a SHA256 hash of their DH key, and is therefore guaranteed to be unique
and available. For Internet-based applications, a server, such as Adobe Media Server or the Cirrus 2
service, is required to connect and authenticate clients for any communication to take place. After the
clients have been authorized, data can be transmitted between peers via RTMFP, which is a 128-bit
encrypted protocol. For additional security, RTMFP Groups can be configured to require authentication
before allowing data to be posted to the group. Before allowing a P2P connection, Flash Player requests
explicit authorization by the client.
When to use RTMFP and peer-assisted networking
RTMFP is a natural choice for real-time communication and streaming when massive scale is needed. It
eliminates the need for huge server and network infrastructures to share large amounts of data. Examples
of use cases include the following:
Webcam chat rooms
VoIP
Live customer support
Dating sites
Company-wide communication
Swarming file delivery (see /wiki/Segmented_downloading)
Massive multiplayer games
Key RTMFP concepts
RTMFP communication is based on User Datagram Protocol (UDP). It is always encrypted and can traverse
NATs and firewalls. UDP supports a lossy transmission of data, which is useful for low-latency audio, video, and
data delivery. RTMFP is a managed and controllable protocol that requires a server to always be present to
perform client introductions and eliminate network probing. RTMFP has unique IP mobility functionality that
allows a connection to be maintained even if the client changes networks, such as Wi-Fi networks or mobile
towers. RTMFP can be used to support unicast communication as well as IP multicast and multicast fusion
broadcasts.
Adobe® Media Server 5 White Paper
21
Comparing RTMP and RTMFP
To clarify when it is best to use RTMFP rather than RTMP, it can be useful to examine their differences
and similarities. The following figure illustrates the basic topology of RTMP, basic RTMFP peer-assisted
networking, and RTMFP Groups.
RTMP
Traditional RTMP streaming and
communication with unicast model
RTMFP P2P Networking
RTMFP in Flash Player 10.0 or Cirrus 1
RTMFP Groups
RTMFP in Flash Player 10.1 or Cirrus 2
Traditional RTMP streaming requires
a client to receive all data from a
centralized server cluster. Scale is
achieved by adding more servers.
First generation of RTMFP in Flash
Player 10.0 supported rendezvous,
with Flash Media Enterprise Server
4.5 for introduction services. Media
was always sourced from the
publishing peer.
Second generation of RTMFP
supporting groups in Flash Player 10.1
and later, with Adobe Media Server 5
Extended for introduction services.
Supports application-level multicast
and reduces the load on the source
publisher.
Figure 4
Evolution of media and communication delivery on the Flash Platform
Key differences between RTMP and RTMFP
RTMP is a unicast delivery method. It simply delivers streams from a server to individual connected clients.
Unicast consumes a large amount of network resources. For example, a 1 MBps stream delivered to 1,000
clients requires 1GB upstream from the server, which is very CPU- and network-intensive.
While RTMFP does support unicast delivery, its benefit lies in its multicast support. Native IP multicast
reduces the network load in the enterprise by distributing the data using customized network hardware.
However, reducing network load in this way does require a hardware investment. Flash Media Server 4
introduced multicast fusion support, which eliminates this hardware investment by offloading the data
delivery to peer-assisted networking, enabling clients consuming a stream to help distribute it to others on
the network.
RTMP is based on Transmission Control Protocol (TCP), whereas RTMFP is based on UDP. TCP is lossless;
each data packet is guaranteed to arrive in the same order it was sent. UDP has no ordering of packets and no
guarantee that the data will arrive at all, which makes RTMFP more lightweight and faster but less reliable than
RTMP. However, some routers do not allow UDP traffic, so it might be necessary for developers to fall back to
RTMP.
RTMP is not encrypted by default, but it can be encrypted using RTMPe (128-bit) or RTMPS (SSL
encrypted). RTMFP communication is always 128-bit encrypted. RTMP can utilize additional content
protection, such as Adobe Access file encryption along with SWF verification.
Similarities between RTMP and RTMFP
Both RTMP and RTMFP can be used to deliver live and on-demand video, audio and data streams. They
both provide low-latency real-time communication, powering applications such as videoconferencing, text
chat, live broadcasts, multiplayer gaming, and live support. They both offer stream encryption.
Adobe® Media Server 5 White Paper
22 Comparing video delivery methods
The following tables provide an at-a-glance reference to the various delivery methods available with
Adobe Media Server, to help guide you to the best solution for your specific application.
Delivery comparison for video on demand
The following table compares the video delivery techniques for VOD with Adobe Media Server.
Mobile and
devices
Not
recommended
because file
sizes are large
and hardware
acceleration
isn’t available.
Not supported
MPEG-TS
streaming
format
supported.
H.264
required.
Flash Player 10.1 and later and AIR supported
on a wide array of devices. Hardware acceleration
available for optimal playback. H.264recommended.
Flash Player
10.1 and later
and AIR
supported on a
wide array of
devices.
Enables
bandwidth
detection and
bitrate
switching over
RTMFP
connections.
128-bit
encryption
Adaptive
bitrate
Not supported Enables
bandwidth
detection and
bitrate
switching over
RTMP
connections.
Provides
inherent
protection
because the
video file is
never cached.
Additional
options
include:
encryption
• Real-time
protection
with RTMPE
• SWF
verification
Enables
bandwidth
detection and
bitrate
switching over
HTTP.
Protected HDS
and Adobe
Access support
Enables
bandwidth
detection and
bitrate
switching over
HTTP.
Protected HLS
Content
protection
Not supported
Adobe Access
support
• Adobe Access
OSMF Not supported
Use OSMF to
build custom
players or use
prebuilt Flash
Media
Playback or
Strobe Media
Playback.
Plug-in
architecture
enables easy
extension of
player features
and integration
with third-
party APIs.
Use OSMF to
build custom
players or use
prebuilt Flash
Media
Playback or
Strobe Media
Playback.
Handles RTMP
connection
and supports
adaptive
bitrate
delivery.
Recommended
approach to
implementing
HTTPDynamic
Streaming. Use
OSMF to build
custom players
or use prebuilt
Flash Media
Playback or
Strobe Media
Playback. Pass
in manifest file
URL. Supports
adaptive bitrate
delivery.
Not supported
Supports F4M
multicast
manifests
Adobe® Media Server 5 White Paper
23
Encoding Video and
audio is
encoded on
import into
Flash using a
Sorenson
Spark or VP6-E codec.
Alternately,
FLV files
(encoded
elsewhere) can
be imported
and placed on
the Flash
Timeline
(re-encoding is
not necessary).
Video files are
encoded in
either the built-in or
standalone
version of
Adobe Media
Encoder,
through Adobe
Media Encoder
and a
third-party
nonlinear
editing or
encoding
product, or
using a
standalone
video
encoding
application
such as
Sorenson
Squeeze or
On2 Flix.
SWF and
video files are
stored
separately,
resulting in a
smaller SWF
file size. Video
delivered via
progressive
delivery is
stored in
memory and is
not
recommended
for large video
assets.
Starts relatively
quickly after
enough of the
video has
downloaded to
begin
playback.
Same as
progressive
delivery. In
addition, you
can capture
and record live
video feeds
from client-side
webcams or
DV cameras, or
using Adobe
Flash Media
Live Encoder.
Live encoding
variables such
as bitrate,
frames per
second, and
video playback
size, can be
controlled
program-
matically.
File Packager
prepares
prerecorded
media, and
Live Packager
prepares live
RTMP streams.
These utilities
create MP4
fragment
compliant files
(F4F) and
generate an
XML-based
manifest file
(F4M).
iOS stream
packager
automatically
creates media
fragments
(M2TS) and
manifest file
(M3U8) on
demand when
stream is
requested by
the client.
Same as
progressive
delivery. In
addition, you
can capture and
record live
video feeds
from client-side
webcams or DV
cameras, or
using Adobe
Flash Media
Live Encoder
SWF File Size
SWF files
contain both
video and
audio data as
well as the
playback
interface,
resulting in a
single,
substantially
larger file
size.
Same file size as progressive
delivery.
N/A Same SWF file
size as
progressive
delivery.
Start Time
Large SWF files
often require
users to wait
before the video
starts playing,
resulting in a
negative user
experience.
Immediate.
The fastest
way to go from
initial load to
actually
playing the
video.
Quick start. Begins to play after
the manifest file has been read
and the first fragment data is
received.
Quick start.
Begins to play
after the
manifest file
has been
read, the peer
connections
have been
made, and the
first fragment
data is
received.
Adobe® Media Server 5 White Paper
24
Timeline
Access
When
embedded in
the Flash
Timeline,
video appears
on individual
frames and
can be treated
like any other
object on the
stage.
Each time the
SWF is
published or
tested, the
entire video
file is
republished.
Changes to
video files
require
manually
reimporting
the files into
the timeline.
N/A
Video is played back only at runtime. Individual
frames are not visible on the stage. Timeline events
can be triggered at selected times during video
playback using ActionScript.
Video is played
back only at
runtime.
Individual
frames are not
visible on the
stage.
Publishing
Video files are
only
referenced at
runtime.
Publishing
SWF files is
much faster
than
embedded
video. Video
files can be
updated or
modified
without
recompiling
the SWF file.
Same as
progressive
delivery. You
can
dynamically
pull video files
from virtual
locations, such
as your storage
area network
(SAN), a FVSS,
or other CDN.
Content must
be packaged
into F4F
format.
Manifest files
can be
updated with
new F4F file
information.
Content is
automatically
packaged by
Adobe Media
Server. To
update media,
new files must
be uploaded to
Adobe Media
Server and the
servers’ media
cache must be
cleared.
Content can
also be
prepackaged
using the file
packaging
utilities
included with
Adobe Media
Server.
Content must
be packaged
into M3U8
format.
Manifest files
can be
updated with
new M2TS file
information.
Content is
automatically
packaged by
Adobe Media
Server. To
update media,
new files must
be uploaded to
Adobe Media
Server and the
servers’ media
cache must be
cleared.
Content can
also be
prepackaged
using the file
packaging
utilities
included with
Adobe Media
Server.
Same as
RTMP
streaming.
Frame Rate Video frame
rate and SWF
movie frame
rate must be
the same.
The entire
SWF file must
be downloaded
before user
can seek or
navigate the
video.
The video file can have a different frame rate than
the SWF file. Live video capture has programmable
control over frame rate.
No restrictions
on frame rate.
The video file
can have a
different frame
rate than the
SWF file.
User can seek
anywhere at
any time.
Seek and
navigation
ability
User can only
seek to
portions of the
video that
have been
downloaded.
User can seek anywhere at any
time. New buffer controls enable
smooth playback during
reconnection if connection is lost.
Instant replay and other
advanced play functionality.
User can seek
anywhere at
any time.
Adobe® Media Server 5 White Paper
25
Content
Delivery
The entire
SWF file must
be downloaded
to the client via
HTTP and
loaded into
memory to play
back video.
Video files are
progressively
downloaded
via HTTP,
cached, and
then played
from the local
disk. The
entire video
clip doesn’t
need to fit in
memory.
Improved
performance
over
embedded
SWF video
with higher
resolution and
reliable audio
synchroni-
zation. Provides
best image
quality, which
is limited only
by the amount
of available
hard drive
space on the
playback
system.
Flash Player 7
and later,
including
Flash-enabled
mobile devices
Video files are
streamed from
Adobe Media
Server via
RTMP,
displayed on
the client’s
screen, and
then discarded
from memory
in a play-as-
you-go
method.
Improved
efficiency from
a network load
perspective,
with optimal
bitrate delivery
on an
as-needed
basis to as
many
customers as
necessary.
Manifest and video fragment files
are downloaded via HTTP,
cached, and then played from the
local disk. The entire video clip
doesn’t need to fit in memory.
Video files are
streamed
between
clients via
RTMFP,
displayed on
the client’s
screen, and
then discarded
from memory
in a play-as-
you-go
method.
Lightest load
on the
network, but
can introduce
some latency.
Playback
Performance
Audio and
video sync is
limited. Sync
between audio
and video
suffer after
approximately
120 seconds of
video. Total file
duration is
limited to
available RAM
on the
playback
system.
Like RTMP streaming, optimal
bitrate can be delivered. Network
efficiencies of standard HTTP
server and network hardware can
potentially decrease overall cost
of delivery.
Compatibility
Flash Player 6
and later,
including
mobile devices
Flash Player 6
and later,
including Flash-enabled mobile
devices
Flash Player
10.1 and later
and AIR 2.0
and later,
including
mobile devices
HTML5, native
iOS playback,
or AIR
Flash Player
10.1 and later
and AIR 2.0
and later,
including
mobile devices
Adobe® Media Server 5 White Paper
26 Delivery comparison for live streaming
The following table compares the video delivery techniques available for live streaming with Adobe Media
Server. Progressive download and embedded video do not support live streaming.
Video
source
Adobe Media Live Encoder, local webcam or DV camera in Flash Player, or third-party Adobe Media
encoder. Visit /products/premiere/ for compatible devices. Live Encoder
Could also be a server-side VOD stream broadcast as live. or third-party
encoder.
Provides
inherent
protection
because the
video file is
never cached.
Additional
options
include:
oReal-time
Adobe Access
encryption
oReal-time
protection
with RTMPE
oSWF
verification
oRTMFP
encrypted
delivery
Media is
cached;
Protected HDS
or Adobe
Access 2 or
later is
required for
protection.
RTMFP protocol is encrypted. Internal network is
used. Adobe Access 2 or later supported.
Protected
HTTP Live
Streaming
Content
protection
Video player
Custom player applications, OSMF-based players (Flash Media Playback,
Strobe Media Playback or custom) in Flash Player or AIR.
Port 1935 and
RTMP
required. For
caching,
additional
FMS servers
are required.
Standard
HTTP caching
technology
can be used.
For media
packaging,
FMS is
required at
the ingest.
Multicast-
enabled
routers
required. If
WAN is not
multicast-
enabled, an
additional
FMS is
required to
replicate.
UDP-enabled.
Internal
network must
be tuned to
accept
multicast
traffic.
UDP-enabled
with ports
open.
Network
partitioning
may be
required to
optimize data
flow.
Both IP and
application–
level multicast
requirements.
HTML5 or
native iOS
playback
Standard
HTTP caching
technology
can be used.
For media
packaging,
FMS is
required at
the ingest.
Network
hardware
Firewall
Traversal
Good
traversal. Port
80 tunneling
available if
needed.
Uses standard
HTTP delivery
protocol.
Might be
restricted.
RTMFP used
to open P2P
connection
between
clients.
Flexible
firewall
traversal. Uses
P2P over
RTMFP if
network isn’t
configured for
IP Multicast
traffic
Uses standard
HTTP delivery
protocol.
Adobe® Media Server 5 White Paper
27 Live RTMP
streaming
Live HTTP
Dynamic
Streaming for
Adobe Flash
(HDS)
Higher latency
due to
real-time
fragmenting
process and
inherent
latency of
HTTP delivery
(vs. RTMP).
Dynamic
Streaming
enables
bandwidth
detection and
bitrate
switching over
HTTP
connections.
RTMFP IP
multicast
RTMFP RTMFP
HTTP Live
Streaming for
Apple iOS
(HLS)
Higher latency
due to
real-time
fragmenting
process (a
minimum of
25 seconds
should be
expected).
Adaptive
bitrate
streaming
enables
bandwidth
detection and
bitrate
switching over
HTTP
connections.
Not
supported.
Latency Lowest
latency
Latency of 5-8 seconds should be expected for
multicast streams, based on network
configuration and buffer settings.
Adaptive
Bitrate
Dynamic
Streaming
enables
bandwidth
detection and
bitrate
switching over
RTMP
connections.
Not supported. Multicast supports delivery of a
single stream only.
DVR
functionality
Supported. Pause and rewind
live streams
Not supported.
Video Player Development
Unlike other video delivery technologies, which just present prebranded players to your viewers, Adobe
Media Server 5 integrates with Flash Player, AIR, and even HTML5, allowing you to create completely
customized playback interfaces.
Figure 5
The Open Source Media Framework simplifies video player development.
The Open Source Media Framework (OSMF) provides a standards-based structure for building custom
video players, enabling developers to take advantage of the latest Flash Platform features and delivery
methods without the heavy lifting of coding from scratch. If a simple branded player is all that is needed,
Adobe Media Playback and Strobe Media Playback provide prebuilt solutions built on OSMF. Whether it’s
a totally custom player built on OSMF, or one of the prebuilt players, deploying full-featured playback
applications is simpler than ever. For more information about OSMF, visit .
Adobe® Media Server 5 White Paper
28 Glossary
Adaptive bitrate—Using bandwidth detection and processor performance measurement to deliver the
most appropriate bitrate stream to a client, switching between bitrates as needed during playback..
Adobe AIR—Cross-platformruntime that lets developers use their existing web development skills in HTML,
Ajax, Flash technology, and Flex to build and deploy RIAs to the desktop.
Application-level multicast—Sometimes referred to as P2P multicast, this delivery method provides an
optimized stream distribution among peers, which can result in a bandwidth cost-savings. Participating peers
organize themselves into an overlay topology for data delivery. Each edge corresponds to a unicast path
between two peers in the underlying Internet. All multicast-related functionality is implemented at the peers
instead of at routers. The goal is to construct and maintain an efficient overlay for data transmission. The
original stream can be distributed from a client or from Adobe Media Server. This is referred to as application-level because the multicast delivery is being enabled by Flash Player or AIR runtime, rather than hardware.
Bandwidth—Amount of throughput for a server or client computer. Usually measured in megabits per
second (Mbps) or kilobits per second (kbps). A typical, wired Ethernet connection is 100Mbps, and Wi-Fi is
54Mbps. Server and client bandwidth limits determine how much video can be served or received.
Buffer—Amount of video stored in RAM on the client computer. The larger the buffer, the smoother the
video plays back. The buffer is never written to disk.
Client—Consumer connecting to server via the Flash Player, AIR application, or iOS.
Codec—The compression algorithm used to encode a video or audio file. Flash uses the Sorenson Spark,
On2 VP6-S, On2 VP6-E, or H.264 codec for video, and Nellymoser, MP3, AAC, or Speex for audio. Short
for “code/decode,” the decoding part must be present in the player to play back video using a specific codec.
Connection—When clients are streaming video, they consume one connection. Multiple clients streaming
at the same time is referred to as simultaneous connections.
Content—Video, audio or data streamed from Adobe Media Server.
Content delivery network (CDN)—A company that offers streaming services and bandwidth so that
customers do not need to set up and install their own servers.
Digital Rights Management (DRM)—Video encoded with DRM can be sold and protected against
stealing and unauthorized sharing.
Encoder—Hardware or software that compresses or transcodes video from one format to another.
Enhanced RTMP (RTMPe)—Encrypted RTMP supported in Flash Player and AIR, that increases security
and performance.
Flex—Cross-platform, open source framework for creating RIAs that run identically in all major browsers
and operating systems via Flash Player/AIR.
Flash Media Live Encoder—Free desktop application for Windows and Mac OS that connects to Adobe Media
Server and allows you to stream live video and audio to Flash Player, AIR, and iOS.
Flash Media Playback (FMP)—Based on Open Source Media Framework, FMP is a free, standard
media player for the Adobe Flash Platform that is hosted by Adobe. It can be used by any website with
only a few lines of HTML. Its extensible plug-in architecture enables easy integration with content delivery
networks (CDNs) and advertising platforms, as well as support for analytics, additional third-party services,
and the latest delivery methods. (For an open source, self-hosted version of Flash Media Playback, see
Strobe Media Playback.) To get started go to: /products/flashmediaplayback/
Adobe Video & Advertising Solution Partners—Partner program that helps promote a strong
ecosystem around Flash technology and Adobe Media Server.
H.264—Industry-standard video codec. Currently one of the most commonly used formats for the
recording, compression, and distribution of high definition video. Supported in Flash Player 9 and later.
Usually combined with AAC for audio.
Adobe® Media Server 5 White Paper
29
HTTP Dynamic Streaming—Delivery method that enables an adaptive-bitrate, protected streaming
experience to Flash and AIR clients, with common HTTP servers, caching devices, and networks. Uses a
standard MPEG-4 fragment container format.
HTTP Live Streaming— Delivery method that enables an adaptive-bitrate, protected streaming
experience to iOS clients, with common HTTP servers, caching devices, and networks. Uses
iOS- compatible MPEG-4 fragment container format.
IP multicast—Network-efficient delivery method that uses existing multicast-enabled network hardware to
deliver large internal broadcasts without overwhelming the network. Multicast-enabled routers create
optimal distribution paths for data sent to a multicast destination address. The most common use case is
live video, but it can be used to deliver on-demand video.
Live—Real-time streaming of content, typically from a camera source, using Flash Media Live Encoder,
Flash Player, or a third-party encoder.
Latency—How long it takes for a packet of data to get from one point to another.
Multicast address—IP address that identifies zero or more computers in a network simultaneously. An IP
multicast address can be any IPv4 or IPv6 multicast address.
Multicast fusion—Adobe’s innovative combination of application-level multicast and IP multicast. Used
cooperatively for a single stream. Allows for distribution of video to internal clients via IP multicast, and
uses those clients to help distribute to clients outside of the multicast-enabled internal network.
Open Source Media Framework (OSMF)—An ActionScript 3 framework that simplifies the development
of media players by allowing developers to assemble components to create high-quality, full-featured
video playback experiences. This open framework enables development focused on web-based video
monetization, with lower costs and faster turnaround. To get started go to: .
On2 VP6—Video codec available for playback since Flash Player 8, offering high-quality, lightweight, full-screen playback. VP6-S is a simplified version of the codec that is ideal for delivery of high-quality video
to older computers (available in Flash Player 9 and later). VP6-E, the original codec that shipped with
Flash Player 8, is slightly higher quality, thus requiring more processing power for playback.
Protected HTTP Dynamic Streaming— A scalable delivery method for encrypted content over HTTP to
Flash Player and AIR clients, without a DRM License Server. Use with SWF Verification for further
protection.
Protected HTTP Live Streaming—A scalable delivery method for encrypted content over HTTP to iOS devices
such as iPad and iPhone, without a DRM License Server. Uses AES-128 wire encryption over SSL. FMS can
bind playback only to Apple devices to add further protection.
Publishing point—Directory on Adobe Media Server where customers can place video and audio, or
publish live video.
Real Time Media Flow Protocol (RTMFP)—Adobe’s proprietary peer-assisted communication protocol
supported in Flash Player 10 and later and AIR 1.5 and later.
Real Time Message Protocol (RTMP)—Adobe’s proprietary method of communication between Flash
Player and AIR clients and Adobe Media Server.
Quality of service (QoS)—Refers to the quality of the consumer’s playback experience.
Solution provider—Consulting and enablement organizations that provide advanced knowledge of
Adobe Media Server and Flash technology, and their integration over multiple devices.
Sorenson Spark—Original video codec in Flash Player 6 and 7. An encoder for this codec is built into
Flash Player, allowing for webcam broadcast and archiving when used with Adobe Media Server.
Strobe Media Playback (SMP)—Based on Open Source Media Framework, this compiled SWF allows
you to get up and running quickly vs. spending time on technical details. Full source code is available for
download and customization. Allows designers, content owners, enterprises, and developers to get started
easily with an out-of-the-box, feature-rich media player. To get started, go to: /strobe_
.
Adobe® Media Server 5 White Paper
30
Transcoding—Conversion from one video format to another. Usually transcoding allows you to change the
codec. Quality is lost each time a file is transcoded.
Video on demand (VOD)—Delivery of pre-recorded video streaming.
Adobe® Media Server 5 White Paper
30
Online Resources
AMS Product Page /go/ams
AMS Technical Guide /go/ams_techguide
AMS Developer Center /go/ams_devcenter
AMS User Group /go/ams_usergroup
AMS Forum /go/ams_forum
Adobe Media Cookbook /adobe_media
Hardening guide for Flash Media /devnet/flashmediaserver/articles/hardening_guide. html
Server
Transitioning from Microsoft /devnet/flashmediaserver/articles/wm_flash_
Windows Media to the Adobe transition_
Flash Platform
Eliminating the single point of /devnet/flashmediaserver/articles/origin_redundancy.
failure with origin redundancy in html
Flash Media Server
Firewall deployment /devnet/flashcom/articles/firewall_
Performance tuning FMS
/devnet/flashmediaserver/articles/performance_
tuning_
Video encoding and transcoding /devnet/flashmediaserver/articles/encoding_
recommendations for HTTP
Dynamic Streaming on the Flash
Platform
Large-scale streaming deployments /devnet/flashmediaserver/articles/fmis_largescale_
with FMS 3.5
Understanding the MPEG-4
/devnet/video/articles/mp4_movie_
movie atom
Adobe Access 4 /go/adobeaccess
DRM and digital media /devnet/flashmediaserver/articles/beginner_vod_fm3. html
protection with Flash Media
Server
Video content protection /devnet/flashmediaserver/articles/protecting_video_
measures enabled by
Flash Media Server
Beginner's guide to streaming /devnet/flashmediaserver/articles/beginner_vod_fm3. html
video with Flash Media Server
Understanding the difference /devnet/flash/articles/flv_
between progressive download
/products/hdvideo/supported_technologies/streaming.
and streaming video
html
Live multicast streaming using /devnet/flashmediaserver/articles/multicast_
OSMF streaming_
Creating a simple multicast video /devnet/flashmediaserver/articles/multicast_player_
player using OSMF
Webcasting live video with Flash /devnet/flashmediaserver/articles/webcasting_fme.
Media Live Encoder html
Adobe® Media Server 5 White Paper
31
Adobe Systems Incorporated345 Park AvenueSan Jose, CA 95110-2704
USA
Exploring Flash Player support /devnet/flashplayer/articles/hd_video_flash_player.
for high-definition H.264 video html
and AAC audio
Beginner’s guide to security features /devnet/flashmediaserver/articles/beginner_security_
in FMS 3.5
Live dynamic streaming and DVR /devnet/flashmediaserver/articles/live_dynstream_dvr.
for non-developers html
Open Source Media Framework
Using peer-to-peer applications /devnet/flashmediaserver/articles/p2p_apps_cirrus_
on the Adobe Flash Platform
Flash 411: FMS /watch/flash-411/hookin-up-with-fms
F4V/FLV Specification /devnet/
Manifest (F4M) Specification
/nf/redirect/?path=http%3A///dev/osmf/
specpdfs/
H.264
/ap/products/hdvideo/supported_technologies/h264.
html
AAC
/ap/products/hdvideo/supported_technologies/
HD Gallery /ap/products/hdvideo/hdgallery/
FMLE /go/fmle/
Flash Player /go/flashplayer
Adobe Video & Ad Partners /go/ams_partners
Content Delivery Networks /products/adobemediaserver/partners/cdn
Hardware & Encoders /products/adobemediaserver/partners/encoders
Live Broadcast Services /products/adobemediaserver/partners/broadcast
Digital Media /digitalmedia
Kevin Towes /ktowes
Flash Player /flashplayer
Jens Loeffler
Lisa Larson-Kelley
Stefan Richter
Fabio Sonnati
About the Author
Lisa Larson-Kelley is a developer, consultant, and teacher of subjects related to online media technologies.
She coauthored the book Flash Video for Professionals (Wiley, 2007). Her blog is
.
Adobe, the Adobe logo, Adobe Integrated Runtime (AIR), ColdFusion, Flash, Flash Media Server, and Adobe Media Server are either registered trademarks or trademarks of
Adobe Systems Incorporated in the United States and/or other countries. All other trademarks are the property of their respective owners.
© 2012 Adobe Systems Incorporated. All rights reserved.
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